1. Technical Field
The present invention relates to a piezoelectric vibrating gyro element and a gyro sensor.
2. Related Art
In recent years, the gyro sensor having the piezoelectric vibrating gyro element stored in a container is largely used as a manual moving correction of an image pickup device, and posture control of a mobile navigation system of a vehicle, etc. using a GPS satellite signal.
For example, a so-called double T-type vibrating gyro element is known as the piezoelectric vibrating gyro element in JP-A-2001-12955 and FIG. 1. In this double T-type vibrating gyro element, a detecting vibrating system extended out of a central base portion, and a driving vibrating system of about the T-type are arranged in the central base portion so as to be symmetrical leftward and rightward.
In this piezoelectric vibrating gyro element or the gyro sensor, it is necessary to suitably change the lengths and widths of a vibrating arm for driving, a vibrating arm for detection and a connecting arm to make the piezoelectric vibrating gyro element or the gyro sensor compact and mount the piezoelectric vibrating gyro element or the gyro sensor to a limited space.
In the former piezoelectric vibrating gyro element, the lengths and widths of the vibrating arm for driving and the vibrating arm for detection are equally designed and their respective vibrating frequencies are closely conformed to each other. However, the vibrating frequency of the vibrating arm for detection is influenced by the vibration of the connecting arm and the vibration of the base portion. Therefore, it was necessary to consider the vibrations of the connecting arm and the base portion in the design of the vibrating arm for detection.
Therefore, when the lengths and widths of the vibrating arm for driving and the vibrating arm for detection are changed so as to be different from each other, a suitable construction must be obtained by repeating many vibrating simulations and trials so that much time is consumed.